In windows "Program Files" or "App Data" or "Program Data" folder check or find or search the folders with names like media video player, best video player, easy video player, etc (name simply doesn't matter it could have any program/folder name) sometimes they don't show in the add/remove programs but they still exist on your computer system and you have to check/find/search them and remove them manually (make sure you are also able to see the hidden files and folders), apart from that you may also check/find/search for any toolbar or search engine that you may have installed before the issue started on your computer system and if you find any, simply remove them, you should also go to Task Manager and stop any processes like (sysctl.exe, winsys.exe, systemsearch.exe, systemengine32.exe, topengine.exe, etc), also you may go to 'msconfig' (or even through CCleaner) startup and see if any unknown files are starting automatically (sysctl.exe, winsys.exe, systemsearch.exe, systemengine32.exe, topengine.exe, etc) if you find any just uncheck or disable or delete them. You may also look for programs like iwebar, shopperpro, searchprotect, youtube accelerator, youtube downloader, sense, flv player (somoto), etc or any suspicious programs from companies like goobzo, somoto, etc and if you find any, you must remove them from your computer system completely, You may also clean your Computer System "Registry" (CCleaner is a free Registry and junk-clearing utility for keeping your system clean and optimized and there are many other programs like that) and while trying Malwarebytes or any such softwares make sure you used their most prominent and professional yet "Premium" versions rather than "Trial" versions or at least a trial version with all features activated and with the latest updated database versions. Also check the "LAN Settings" of your browsers and keep it to "Automatically detect settings" unless you are using a proxy server intentionally and try to download an original Microsoft "Hosts" file and replace it with the one on your computer system, you may also try to reset and restore advanced settings (especially in internet explorer) of all your browsers to default, also with the help of CCleaner try to delete all the unwanted, junk files from your computer system, also delete the cookies and temporary internet files as well, also if needed or if possible try to uninstall all your browsers or the one that is effected (if possible delete all the user data as well), you can re-install the browsers again.
Last but not the least, you may restore your system to any restore point that was working perfectly before this popup issue started on your computer system.
Hope this helps.
Peace & Blessings.